I'm having a hard time determining my hen's illness. No respiratory or coccidiosis symptoms. Her poo is sulfur yellow, which is apparently a classic hallmark of Blackhead/Histomoniasis, which is mostly seen in turkeys. She and her sisters do get to free range in the backyard daily and we have lots of visiting birds. Possibly she picked it up from them. Does anyone have any thoughts on what this could be besides Blackhead, and the best treatment? According to another post, a woman treated her turkeys with cayenne powder and it worked. I've been trying that for 2 days with no change in her health or poo.